Synopsis Once in decades a book is published, by mastering which, a reader may feel himself master of the subject. With their vast experience of teaching, writing and research in education, the authors have presented such a book. It covers the courses prescribed in this subject by all the Indian Universities in a comprehensive yet brief format. With lucidity of narration, examples from every day life, analytical presentation, integral approach in controversial matters and actual questions asked in university papers given at the end of each chapter, this work is an ideal textbook for the students and reference work for teachers of the subjects. A comprehensive bibliography at the end shall guide those who wish to study this subject further in more details.